The invention relates to a connecting chain link for link chains having two connecting-link parts which can be displaced with respect to each other by limited amounts in the longitudinal direction of the connecting link, in order to open and close the connecting link, in which the connecting-link parts in each case have two ends which are connected to each other via a longitudinal web and essentially form a quarter circle, in which each connecting-link part has a stub provided with a retaining web at its one end and at its other end has a pocket which is used to hold the stub and the retaining web of the other connecting-link part in each case and is provided with a retaining groove for the retaining web, in which the longitudinal webs of the connecting-link parts have projections directed into the interior of the connecting link, and in which in the closed position the connecting-link parts are secured by at least one locking element against the connecting link being unintentionally opened.
DE 298 11 332 U1 discloses a connecting chain link of the abovementioned type, in which the projections which are directed into the interior of the connecting link each have a transverse web and a transverse groove, and in which, when the connecting link is closed, the transverse web of one connecting-link part in each case grips in the manner of a hook into the transverse groove of the other connecting-link part in each case in order thereby to relieve the load on the stub connections in the region of the rounded heads of the connecting chain link. That is to say, in the known design the hook-shaped projections are used to pursue the aim of absorbing in the centre of the connecting chain link some of the forces which act perpendicularly to the longitudinal axis of the connecting link on the connecting-link parts and attempt to separate the latter from one another. In the known connecting chain link, in order to secure the connecting-link parts against being unintentionally opened, use is made of comparatively thin pins which, after the connecting link is closed, are knocked into transverse holes in the region of the ends of the connecting-link parts. As experience has shown, after a prolonged period of operation, the removal again of the pins for the purpose of opening the connecting link causes considerable difficulties which can be attributed firstly to the formation of frictional corrosion and secondly to the deformation of the pins under load. In addition, the fact that the strength of the connecting chain link is somewhat impaired when the transverse holes are made in the region of the stub connections has proven unfavourable.